Chiral stationary phases and applications in gas chromatography

Abstract

Chiral compounds are ubiquitous in nature and play a pivotal role in biochemical processes, in chiroptical materials and applications, and as chiral drugs. The analysis and determination of the enantiomeric ratio (er) of chiral compounds is of enormous scientific, industrial, and economic importance. Chiral separation techniques and methods have become indispensable tools to separate chiral compounds into their enantiomers on an analytical as well on a preparative level to obtain enantiopure compounds. Chiral gas chromatography and high‐performance liquid chromatography have paved the way and fostered several research areas, that is, asymmetric synthesis and catalysis in organic, medicinal, pharmaceutical, and supramolecular chemistry. The development of highly enantioselective chiral stationary phases was essential. In particular, the elucidation and understanding of the underlying enantioselective supramolecular separation mechanisms led to the design of new chiral stationary phases. This review article focuses on the development of chiral stationary phases for gas chromatography. The fundamental mechanisms of the recognition and separation of enantiomers and the selectors and chiral stationary phases used in chiral gas chromatography are presented. An overview over syntheses and applications of these chiral stationary phases is presented as a practical guidance for enantioselective separation of chiral compound classes and substances by gas chromatography.

Chemical Characterization and Biological Activity of the Essential Oil from Araucaria brasiliensis Collected in Ecuador

“…The EO from A. brasiliensis contained about 10% α-pinene, which was reported to exhibit potent effects against AChE [20,44]. Contrary to our expectations, however, the oil was almost inactive against AChE, whereas it exhibited moderate activity against BuChE.…”

“…The combination of chemical and chiral features of an EO is very useful for assessing its identity and quality. Moreover, interactions with chiral entities, such as enzymes, proteins, and receptors, may vary greatly between enantiomers, causing significantly different biological activities such as those related to pharmacology, pharmacokinetics, metabolism, toxicity, or immune response [44].…”

Enantioselective HS-SPME-GC-MS for Authentication of Natural and Synthetic Strawberry Flavour in Syrups

“…Current literature usually mentions the formation of inclusion complexes [Betzenbichler et Wu et al, 2022]. Anyway, even nowadays there are studies considering inclusion interactions as a factor that can play an important role in enantioseparation [Betzenbichler et al, 2022]. The need for more explicit clarification of the enantioseparation mechanisms is often mentioned, as this would make it possible to prepare even a more universal enantioselector [Cagliero et al, 2015;Engel, 2020].…”

“…Therefore, testing the functionality of chiral selectors by their direct application in the chromatographic analysis of real samples is a significant support in the field of enantioselectivity research. The CP-Chirasil-Dex CB column was chosen for our investigation due to its possible efficiency in separating enantiomers of the investigated enantiomeric pairs, due to the popularity of similar enantioseparating columns in relevant literature [Betzenbichler et al, 2022;Cagliero et al, 2017;de la Peňa Moreno et al, 2010;Schmalzing et al, 1992], as well as because of the results achieved on β-cyclodextrin phases in the analysis of strawberries (Table 1).…”

“…Enantiomeric ratios and characterization of selected chiral volatiles in strawberry syrups(1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) See the legend below Table2for other details. Coelutions were noticed for the results in italics; nj -not judgeable due to coelution.…”